To what extent are hepatic concentrations of heavy metals in Anguilla anguilla at a site in a contaminated estuary related to body size and age and reflected in the metallothionein concentrations?

We explored how hepatic [metal]s in Anguilla anguilla at a contaminated estuarine site are influenced by body size, age and season, and the extent that [Cu], [Cd] and [Zn]s are reflected in [metallothionein (MT)]s. Although each [metal] and [MT] increased significantly with length, weight and age, those biotic variables explained <10% of the variation in each [metal] and only 11–16% for [MT]. Seasonal changes in [Cu] and [Cd] were paralleled by [MT]. The variation in [MT] explained by Cu (42%) was greater than by Zn (16%) and Cd (13%), and seasonally lay between 43 and 69% for those metals collectively. Thus, hepatic [MT] in eels is closely correlated with hepatic [heavy metal]s. However, the great variability among [MT]s for eels of similar sizes and ages, which reflects marked variability in hepatic [heavy metal]s, means that this variable reflects imprecisely the contamination level at a particular site.